What is a legacy system? And how can you integrate one with modern apps

Legacy system integration

Despite the ever-growing adoption of SaaS applications, organizations small and large still rely on legacy systems to manage key business processes.

You might even be using legacy systems in your day-to-day work, whether it’s your ERP system or your database that hosts critical client or employee information.

But how do you know when a system is truly legacy or not? What are some of the drawbacks these systems present? And why is integrating them with your modern apps often the best approach in managing these types of systems?

We’ll tackle each of these questions throughout this page. That way, you’ll be able to identify the legacy systems at your organization and decide whether—as well as how—to integrate them with the rest of your tech stack. 

What is a legacy system?

A legacy system is a type of system that’s been around at an organization for several years and that’s been kept fairly stagnant. The system doesn’t use modern, web-based UI capabilities, or have technology advancements around integrating with other systems. And typically, it’s on-prem.

Legacy systems can take a multitude of forms, including databases, ERP systems, CRM applications, and HCM systems; they’re also used by organizations in a variety of industries, with the list including finance, retail, government, manufacturing, among other sectors.  

Finally, it’s also worth noting that legacy systems can vary widely in their technical capabilities. For example, some may provide APIs, while others don’t offer any type of connectivity.

With this background in mind, let’s explore several drawbacks of using legacy systems.

Related: The meaning of native integration and its pros and cons

Disadvantages of using legacy systems

Though there are several you can point to, we’ll focus on a few important ones.

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  • They create security concerns for your organization. Legacy systems may have been originally designed to meet data protection and privacy standards that are no longer in place or that are outdated. This, coupled with the system’s inability to keep up with more recent and future measures, makes them ineffective at meeting your data protection and privacy needs—as well as your clients’.

Also, in many cases, the vendor that originally provided the legacy system is no longer supporting it. When that’s true, the vendor won’t provide security patches that address security vulnerabilities.

A myriad of real-world examples underscore the significance of this issue. For instance, in 2015, there were a pair of cybersecurity hacks on legacy government databases that affected millions of Americans. A variety of information—from social security numbers to residency histories—was stolen, leading the victims to be highly vulnerable to additional threats.

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  • They can negatively impact business continuity. As your legacy applications become more and more customized, the expertise required in using them magnifies. 

This quickly becomes an issue when the few employees who know how to use them leave the organization. Why? Because the rest of your employees will likely be afraid of touching them (for fear of breaking them). Ironically, this only leads these systems to become more brittle, increasing their chances of breaking with little possibility for repair—especially when they’re no longer supported by their vendors. 

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Despite these shortcomings, many legacy systems still offer value for the business (maybe even more than certain modern applications). In addition, the costs of migrating away from them can be inordinately high, often rising to tens of millions of dollars. 

In cases where at least one of these is true, your best bet is to integrate your legacy systems with your modern tech stack. We’ll explain why, but before we do, let’s define legacy system integration.

Related: How to modernize legacy systems

What is legacy system integration?

It’s the process of connecting a legacy system with modern, cloud-based applications. Depending on the legacy system and its capabilities, this can be done through APIs, a database connector, or files.

Why you should integrate legacy systems with modern technology

Here are 3 critical reasons to consider:

1. As mentioned previously, many legacy systems still meet business needs, whether it’s tracking data, generating reports, etc. 

You can continue leveraging the functionality from these still-valuable systems while avoiding the clunky user interface they provide users. This simply involves using an enterprise automation platform to connect these systems with apps that use a modern UI—such as those built in a platform like OutSystems. 

2. Legacy applications may offer poor reporting capabilities on their own. But by integrating them with a platform like Snowflake, you can pull data out of the former and into the latter. This, in turn, lets you analyze and report on the data faster and more comprehensively.

3. Syncing legacy applications with the rest of your tech stack enables you to automatically move records and sync data across systems. This not only removes data silos and prevents app hopping, but it also paves the way for automating workflows end-to-end across processes in HR, finance, sales, marketing, etc.

Related: The benefits of business integration

Your options for integrating legacy systems with modern apps

Once you’re set on integrating your legacy systems, you might find yourself wondering how you can go about doing so.

You have a few options, but the one you choose should depend on the nature and capabilities of the legacy system.

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  • If the legacy system offers an API, it’s your best option for building the integration.

Using its API and an enterprise automation platform, you can easily connect the legacy system with your apps and then utilize triggers and actions that allow you to sync or move data in near real-time. 

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Learn more about the types of triggers you can use.

  • If you need to integrate with the back-end database of a legacy system, you can use a database connector provided by an enterprise automation platform.

This lets you export the data in a way that’s also near real time. But there are two drawbacks to keep in mind.

One being that you need to understand the data model of the legacy system in order to translate it in the way you want to downstream systems.

For example, say a database has a field labeled as invoice type. One type, customer invoice, is stored as #1, while supplier invoice is labeled as #2. Unless you’re well-versed in this data model format, you simply won’t know what those numbers correspond to, which prevents your team from using them (or, just as bad, using them incorrectly in downstream systems).

Another drawback is that the data can (and should) only be read from the database. Reason being, adding data into it would jeopardize your team’s ability to preserve data consistency.

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Related: A guide to using an integration platform as a service (iPaaS)

  • If files are available, you can use them to import data to and export data from the legacy system.

This approach is generally reliable, but unlike the other two integration approaches, it can’t sync data in real time. Instead, data would be extracted or imported on a recurring, time-based cadence, such as once every day or once every few hours.

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Ready to integrate your legacy systems with your modern apps?

Workato, the leader in enterprise automation, offers multiple options to pick from. You can learn about them by speaking with one of our automation advisors.

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About the author
Jon Gitlin Content Strategist @ Workato
Jon Gitlin is the Managing Editor of The Connector, where you can get the latest news on Workato and uncover tips and frameworks for implementing powerful integrations and automations. In his free time, he loves to run outside, watch soccer (er...football) matches, and explore local restaurants.